Seed traits and phylogeny explain plants' geographic distribution

[摘要] Understanding the mechanisms that shape the geographicdistribution of plant species is a central theme of biogeography. Althoughseed mass, seed dispersal mode and phylogeny have long been suspected toaffect species distribution, the link between the sources of variation inthese attributes and their effects on the distribution of seed plants arepoorly documented. This study aims to quantify the joint effects of key seedtraits and phylogeny on species distribution. We collected the seed mass andseed dispersal mode from 1426 species of seed plants representing 501genera of 122 families and used 4 138 851 specimens to model speciesdistributional range size. Phylogenetic generalized least-squares regressionand variation partitioning were performed to estimate the effects of seedmass, seed dispersal mode and phylogeny on species distribution. We foundthat species distributional range size was significantly constrained byphylogeny. Seed mass and its intraspecific variation were also important inlimiting species distribution, but their effects were different amongspecies with different dispersal modes. Variation partitioning revealed thatseed mass, seed mass variability, seed dispersal mode and phylogeny togetherexplained 46.82 % of the variance in species range size. Although seedtraits are not typically used to model the geographic distributions of seedplants, our study provides direct evidence showing seed mass, seed dispersalmode and phylogeny are important in explaining species geographicdistribution. This finding underscores the necessity to include seed traitsand the phylogenetic history of species in climate-based niche models forpredicting the response of plant geographic distribution to climate change.

[学科分类] 大气科学